The Bride-to-Be

Diana – then, in 1980, a kindergarten teacher at the exclusive Young England school in Pimlico, London – keeps a close hold on two of her students in one of the first shots of the future princess, which would also be among her first controversies. The backlit Diana didn't realize her skirt was transparent.

The Royal Engagement

In the first photograph of the royal couple, Charles, Prince of Wales, then 32, poses with his fiancée, Lady Diana Spencer, 19, outside Buckingham Palace on Feb. 24, 1981 – just moments after announcing their engagement. Nearly three decades later, Diana's son William proposed to longtime girlfriend Kate Middleton with his late mother's iconic engagement ring.

The Princess Bride

The train of the Princess's Emmanuel ivory taffeta and antique lace wedding gown was 25 feet long, and it took her three and a half minutes to walk down the carpeted aisle at St. Paul's. The planning of the dress was a lonely affair, as designer Elizabeth Emanuel recalled, "Nobody really came to fittings with her."

The Big Event

More than 600,000 people crowded the streets of London to see Lady Diana Spencer and Prince Charles make their way through the streets of London on July 29, 1981, their wedding day. Their international audience was even larger: Almost 1 billion people watched from home.

Sleeping Beauty

"I felt compelled to perform," Diana had said, "To do my engagements and not let people down." Still, she filled her schedule – but couldn't help but fall asleep during a 1981 event. (It was later revealed that, at the time, she was pregnant with William.

Baby Talk

"I felt the whole country was in labor with me," Diana said of her pregnancy with William, who was born June 21, 1982. Diana stayed only a day in the hospital. "It had been quite a difficult pregnancy," she later admitted. "I hadn't been very well throughout it, so by the time William arrived it was a great relief."

A Full Dancing Card

During the Waleses' first visit to the U.S., in 1985, Diana danced at the White House with John Travolta, while Prince Charles chatted up Nancy Reagan. Later that night, the Princess waltzed with Neil Diamond and Clint Eastwood.

The Game's Afoot

Amid rumors of living separate lives within their troubled marriage, Diana openly flirted with polo players while her husband looked the other way at a November 1985 polo match in West Palm Beach, Fla.

Reaching Out

The Princess raised awareness and understanding of the HIV virus – then a new and frightening illness – by reaching out and holding hands with an infected man on April 19, 1987. "HIV does not make people dangerous to know, so you can shake their hands and give them a hug," she had said. "Heaven knows they need it."

A Vision in White

No Storybook Ending

"Here was a fairy story that everybody wanted to work," Diana had said about her marriage to Prince Charles. But relations between the two were visibly frosty on Nov. 3, 1992, at a memorial service in Korea. A month later, on Dec. 9, Prime Minister John Major announced their separation. "I desperately wanted it to work," Diana later said. "I desperately loved my husband."

Time to Go Yet?

In Danger for a Cause

The Princess famously donned a flak jacket and a face shield while touring an Angolan mine field, on behalf of the Red Cross, on Jan. 15, 1997. Diana later said that land mines – and the destruction they cause – is "something to which the world should urgently turn its conscience."

A Doomed Romance

"Diana is besotted," PEOPLE reported when the Princess was photographed with her beau, Dodi Fayed, on his father's $32 million yacht off the coast of Sardinia. It would be one of the last photos taken of the couple, who died in a fatal car crash in Paris the following day, Aug. 31, 1997.

A Sad Goodbye

More than a million people lined the streets on Sept. 6, 1997, as Diana's casket made the four-mile-long journey from London's Westminster Abbey to the Spencer family home in Northamptonshire. A card addressed to "Mummy" from Harry, then 12, rested among the flowers.